Air conditioning system for railroad cars



April 11, 1939. w. H. CARRIER AIR CONDITIONING S YSTEM FOR RAILROAD CARSFiled Feb. 21, 1930 i E INVENTOR. L, w- H- M BY WORNEKS.

Patented Apr. 11, 1939 AIR CONDITIONING SYSTEM FOR RAILROAD CARS WillisH. Carrier, Essex Fells, N. J., assignor, by mesne assignments, toCarrier Corporation, Newark, N. J., a corporation of DelawareApplication February 21, 1930, Serial No. 430,210

6 Claims.

This invention relates to methods of and means for cooling andconditioning enclosures, more particularly railroad cars.

The general object of the invention is to provide a system of airconditioning adapted to be installed in a railroad car of conventionaldesign. Inasmuch as the requirements of operation and the traflic loadof a railroad car are rarely constant, and in view of the mobilecharacterof m railroad carriages, the problem of air conditioning thisequipment presents difficulties not ordinarily encountered. Thus, forexample, the usual water supply available in the air conditioning offixed plants is obviously not to be had for use 15 in railroad cars. Asa result, if water is to be used in the system, it must be maintainedand circulated in substantially closed circuits; No regular feed can beprovided nor any additions be made except at periodic intervals forpurposes 20 of replenishment.

A feature of the invention resides in the provision of an airconditioning system having a plurality of substantially closed watercircuits, one of which is used for the conditioning of air and 25another of which is itself changed in character by the action of asupply of air. The water used for conditioning air is refrigerated bymeans arranged to be located in any suitable space in the car. The wateris routed through a condi- 3o tioner designed to intake outside air andto circulate retm'n air in a course through or around the conditioner.

Another feature of the invention, therefore, embraces the design and useof a conditioner 35 served by a plurality of air sources of difierentcharacter. Control instruments are provided so that the volumes ofoutside and return air may be suitably proportioned to make allowancefor variations in outside conditions and in refrigerat- 4 ing load.

' Another object of the invention is to provide a cooling tower of adesign suitable for economical installation in an area ordinarily notused for passenger seating accommodation and whose efil- 45 cientoperation is not dependent upon a continuous .supply of water from anoutside source. Applicant has designed the cooling tower so that itsoperation is a function of outside air conditions and its efilciencyunimpaired regardless of 50 fluctuations in said conditions. The coolingtower may be of a design similar to that of the conditioner used in thesystem, and hence manufacture of conditioning and cooling tower units issimplified and rendered relatively economical.

55 Since the operation of the cooling tower requires an outside airsource, provision is made for routing desired large quantities ofoutside air through the cooling tower. Provision is also made forutilizing return air also, if operating expedience so demands.

A further feature of the invention, therefore, resides in thearrangement of a duct system in combination with a cooling tower,whereby a source of water routed to the cooling tower may be reduced intemperature and changed in character to a substantially fixed degree bycontact with controlled amounts of air whose character may befluctuating.

Further objects and features of the invention covering the arrangementand design of component parts used therein, and resulting in maximumefiiciency and economy of installation and operation will be moreapparent from the following description of one form of the invention, tobe read in connection with the accompanying drawing, in which- Fig. 1 isa diagrammatic illustration of an air conditioning system adapted foruse in a railroad car;

Fig. 2 is a sectional view, to a larger scale, of a unit designed to beused as a conditioner or as a cooling tower; and

' Fig. 3 is a prospective fragmentary viewof a portion of a car, showingan illustrative installation of a cooling tower and its associatedducts.

Considering the drawing, similar designations referring to similarparts, numeral 4 refers generally to the combination of apparatus shownin Fig. 1 and the relation of the various components to each other. Thesystem includes a compressor 5, which may be used for any desiredrefrigerant,

- condensers 6, evaporators la and lb, expansion valve 8, airconditioning unit 9, cooling tower unit It], pumps and auxiliary motorsll, l2 and the usual connecting linesand accessories ordinarily requiredfor completing and assembling the system in an operating arrangement.

In the layout illustrated, any suitable refrigerant, such as ammonia,may be employed and the refrigerant circuit illustrated may be traced ina course including compressor 5, condensers 6, expansion valve 8, inparallel through coils within evaporators la and lb and back to thecompressor.

The water circuit for the conditioning unit is substantially closed andfollows a course, including pump l2, around the coils of evaporator la,through the air conditioning unit, within and around the coils ofevaporator lb, and back to the pump.

The condenser water circuit proceeds from pump II to the condensers,then to the water tower unit l and back to the pump. 4

The pumps may be suitably associated with the traction equipment of thecar and hence will be operated whenever the car is in motion. It

is obvious, of course, that any desired overflow device may be providedas well as connections for replenishing the water supply and otherwiseservicing the apparatus.

Since the system is merely shown in diagrammatic form for illustrativepurposes only, the general scheme of assembly and operation is indicatedwithout including the numerous details usually included in the practicalapplication and installation of the system.

In Fig. 2 unit l3, corresponding to air conditioning unit 9 of Fig. 1includes an outer liquid reservoir I4, inner sump l5, pump l6 andauxiliary spray device II, the pump being mounted on shaft l8 of motorl9. The shaft also mounts a fan 20. Eliminators 2|, are provided forremoving entrained moisture, prior to discharge of the air from the unitto distributing duct 22. Preferably, the unit is located at one end ofthe car. While the unit preferably extends substantially the height ofthe car, it is evident that it may be suitably arranged in any desiredmanner, preferably so that the usual water fountain and lavatoryfacilities may still be provided. The unit I3 is preferably positionedadjacent window 23 of the car. Intake opening 24 of the conditioner isconnected to the window opening by a suitable duct or partition, so thatair from outside may be drawn C through the window and within theconditioner by the suction of fan 20. Intake opening 25 of theconditioner is arranged to draw air from the car through the conditionerwhereas recirculating opening 26 draws air from the car within thecasing in a source by-passing the sprays. In the operation of theconditioning equipment, the pump and fan will be revolved by motor I 9.The pump will draw water supplied to sump l and eject it in the form ofspray through the nozzles of device I! dueto the centrifugal action. Thewater from the spray will drop to reservoir I 4 and thence be removedfrom the conditioner. The

outside air and return air will be routed through the sprays by the fanand discharged to distributing duct22. The condition of the air afteritleaves the sprays, regardless of whether it was originally outside orreturn air, is substantially the same. As the recirculating opening 26allows air to enter, this conditioned air will be mixed with tion isunder automatic control. Thus, the fresh air inlet will be opened morewidely asthe number of people in the car increases. The return inlet 25may be opened when'the temperature in the car tends to rise; while onthe other hand if graduated type may be utilized for temperature andhumidity control purposes.

In Fig. 3 a duct system is provided for removing the air routed throughcooling tower l3. In this arrangement outside air from window 23 will berouted through the cooling tower in the same manner as illustrated inFig. 2. If desired, return air from the car through inlet 28, will alsobe. intaken and routed through the cooling tower in combination with theoutside air. The condenser water will thus be reduced in temperature dueto its intimate contact in the form of spray with the large volumes ofair passed through the cooling tower. If all outside air is used, thewater will be cooled to a point approximating the outside wet bulbtemperature. If return air is also used, the wet bulb temperature of themixture will be the gauge of the cooling effect on the water. It isfound that the di'fierential in temperature between the water at thecondensers and its condition at the cooling tower is substantiallyconstant regardless of outside conditions. In view of the necessity forrouting large volumes of air through the tower, and for reducing flowreslstance to a minimum, applicant provides outlets 29 and 30 at theupper end of the service and toilet space on one side of the car andoutlet 3| at the other side of the car. The duct to outlet 3| isalongthe roof of the car'in the vestibule space and hence inconspicuous.The appearance of the car is left preserved and the interior space iswholly reserved for its usual passenger accommodation purposes.

While applicant is illustrating the assembly of parts and the operationof 'the system as well as that of the conditioner and cooling tower, incertain and definite ways, it should be understood that theillustrations described herein are merely deemed representative. Anyanalogous means for carrying out similar objects are deemed within thepurview of the invention.

Having described my invention, what I claim as new and desire to secureby Letters Patent, is:

1. In an air conditioning system for a railroad c'ar, condensingequipment for effecting heat exchange from a refrigerant used in thesystem, a cooling tower having a reservoir in the bottom thereof, awater-circuit including said condensing equipment and, said reservoir,means for spraying water from said reservoir downwardly through saidtower, another reservoir in the bottomof said tower for receiving thespray, an outlet from said other reservoir leading to the condensingequipment, said reservoirs being located one with-v in the other in thecooling tower.

2. The method of conditioning the air in a passenger vehicle, whichconsists in drawing the air into a unit, passing the air through a coldwater spray in said unit to remove all foreign matter therefrom, andreducing the temperature of the air, regulating its moisture content,all of which is accomplished in said unit, and then distributing theconditioned air at a plurality of the said vehicle, and then cooling thesaid water for reuse and returning it to the spray.

3. The method of conditioning the air in a passenger vehicle, whichconsists in drawing the air into a unit, passing the air through a coldwater spray in said unit. to remove all foreign matter therefrom, andreducing the temperature of the air, regulatingeits moisture content,and

' points into the space occupied by passengers in eliminating theentrained water from the air, all

of which is accomplished in said unit, and then occupied by passengersin said vehicle, removing the heat units from said spray water, andreturning said cooled water to said spray, then dissipating these heatunits-in a cooling tower.

4. The method of conditioning air in a passenger vehicle, which consistsin drawing air into a unit, passing air through a cold water-spray insaid unit to remove all foreign matter therefrom and reducing thetemperature of the air, regulating its moisture content and eliminatingthe entrained water from the air. all of which is accomplished in saidunit, distributing the condifirst inlet, a second inlet for admittingair from' the interior of said car to the interior of said casing, a fanfor drawing upwardly through said casing air intaken through said firstand second means, whereby air intaken through said third V inletbypasses said spray, and means for supplying air intalren through all ofsaid inlets to said 6. A heat transfer device including means forming atower, means forming a reservoir proximate the bottom of said tower,means for supplying liquid to said reservoir, means forspraying liquiddrawn from said reservoir downwardly through said tower, means forrouting gas through said tower in contact with said sprayed liquid,means forming another reservoir within said tower and proximate thebottom thereof for receiving sprayed liquid, said reservoirs beinglocated one within another and being segregated from each other, andmeans for withdrawing liquid from said second-mentioned reservoir.

W. H. CARRIER.

